Sewing-machine shuttle



Jan. l2 1926.

R. N. coRTHELL.

sEwING MACHINE SHUTTLE Filed Feb. 2'?, 1925 Patented Jan. A12, 1926.

ROBERT N. CORTHRLL, or AUBURN, MAINE.

SEWING-MACHINE SHUTTLE.

Application filed February 27, 1925. Serial No. 11,985.

To all lwhom t may concern.'

Be it known that I, ROBERT N. GoR'rHnLL, a citizen ofthe United States, residing at Auburn in the county of Androscoggin and State of Maine, have invented newand useful Improvements kin Sewing-Machine Shuttles, of whichy the following is a' specification. y

This invention relatesA to a shuttle adapted to receive and permit the rotation of a ready-wound bobbin, and provided With a thread-tensioning spring and securing means, fixing the spring to an element of the shuttle in a predetermined position,

` enabling the spring to tension the thread drawn from the bobbin during the stitchforming operation of a sewing-machine.

The object of the invention is to provide a shuttle with a tensioning spring, having means for controlling the bobbin by preventing undesirably free rotation thereof.

This object is attained by providing the tensioning spring with a bobbin-controlling spring integral with the tensioning spring, and adapted and arranged to bear yieldingly on an end face of a bobbin in the shuttle, the tensioning spring and controlling spring being applicable as a unit tothe shuttle, and each being held by said securing means in position to perform its function, so that the operation of securing a tensioning spring in its operative position, also operatively secures a b-obbin-controlling spring, the two springs being adapted to be installed,y in a shuttle in place of the usual spring adapted only to tension the thread. Of the accompanying-drawings forming a part of this specification,-

Figure y1 is a sectional view, onv an enlarged scale, of a shuttle knownas the Singer-Central type, provided with a thread-tensioning spring and a bobbin-con trolling spring, in accordance with my invention.

Figure 2 is a section on line 2-2 of Figure 1. y p

Figure 3 is a. perspective view, showing only the tensioning spring and the bobbincontrolling spring.

Figure 4 is a side view of the end-thrust supporting member shown by Figure 1.

Figure 5 is a section on line 5-5 of Figure 4.

The same reference characters,indicate the same parts in all of theL figures.

12' designates a bobbin-thread Vtensioning spring, adapted tol cooperate in the usual manner with a shuttle element;13, .here shown as a bobbin case separably engaged by well known means witha shuttle body 14. H

The ele-ment 13"is provided. with the usual or any suitable securing means, for fixing the spring 12 in position to perform its usual thread-tensioning function, the usual means includinga tapped orifice 15, in the element 13, and a screw 16, having a shank inserted in an orifice 17 in the spring, and engaging the orifice thread, and a head clamping the spring against the element 13, turning of the spring on the screw being prevented by a tenon 12L on one end of the spring, engaged .with the element '13- as shown by Figure 2. f The tensioning spring kr12y is provided with an integral bobbin-controlling Vspring` 18, adapted and arranged to bear yeldingly on an end face of a bobbin in the shuttle. As here shown, the bobbin is of the readywound type including a paper cop tube 19, and a thread winding 120.

The tensioning spring 12 and the bobbincontrolling spring 18 are formed in a single piece from thin resilient sheet metal, such as tempered steel, the tensioning spring being curved, and the controlling spring` 18 arranged at an angle to the tensioning spring, so that it is held in position toperform its function by the means securing the tensioning spring to the shuttle.

In the Singer-Central shuttle here shown, the element 13, constituting a bobbin case, is provided with a tubular center post 20, receiving a post-21 on the shuttle ody, the bobbin being rotatable on the post 20, as usual. The bobbin-controlling spring 18 extends through an opening 22 in the bobbin case, andY is obliquely arranged, as shown bysFigure 2, so that it extends well accross the bobbin at one side of the center post 20. f

The spring 18 is normally held `by its `rei' silience inl the position shown by dotted lines in Figure 1, and is moved to the full line position, and thus tensioned, by the bobbin. The spring 18, therefore, exerts a retarding pressure on one end face of the bobbin, and presses they opposite end face against an end-thrust bearing on `the shuttle body. Said bearing is preferably a dished disk 23, having a central opening 2li, inl

terrupted by slots 25, so that itswmill` ism fore performed by an independent spring interposed between the head of the bobbn ease and the inner end face of the bobbin.

I claim: A rotary `.sewing machine shuttle which includes `a body having` an end thrustibarbobbineoontrfolling f ing, a bobbin case engaged `with the body1 and: provided with a^` center'` post on `which a bobbin inserted inthe',` ease is rotatable,l thefree ,end of said post being adj aoent the thrustbearingonthev body, a substantially T-s'haped member having its head portion. e conforming to the curvature of and secured against the outer face of the side wall of thebobbin oase, one arm of saidhead constituting a thread tensioning means, and the stem of. said member" extending" through anopening in tlmejvvall of* tliebobbin ease in positionto bearon the innerjend` faceoi5 a bobbintherein and 'press the bobbin" against the thrust `bearing on thefbfocly``"` signature.

ROBERT Ne." oonrnngnr; e 

